The first time David Peralta walked a game off, in September of last year, he took it quite literally. He stood at home plate with the bases loaded and saw four balls before he saw three strikes. There were no sprints around the bases. Much of the conversation after the game was about J.D. Martinez, who’d hit his 16th homer of the month to spark the rally in the ninth inning.

But Monday against the Phillies, Peralta didn’t have to take a backseat to a teammate. He both started the rally — with a solo homer in the ninth to give a lilting Diamondbacks offense some life — and finished it. His second bomb of the evening came in the 14th inning, bouncing off the yellow padding atop the wall in deep left center to give the Diamondbacks a cathartic 3-2 victory.

For Peralta, it was his first walk-off homer — at any level, he said – as well as his first walk-off hit.

“I always wondered how does it feel to hit a walk-off homer, and it’s something you...